Technical Field
The present invention relates to a device for opening bags in mixtures of wastes and a method for opening bags in mixtures of wastes.
Prior Art
A device of the art at issue is, for example, known from the publication EP 0 686 562 B1. The device therein disclosed has groups of tearing elements, which may be moved in such a manner that tearing forces may be generated by relative movement between the tearing elements of different groups. In this instance, the tearing forces result from the fact that the distance between the tearing elements of different groups changes on the basis of the relative movement. In doing so, the tearing elements are suited to transfer the tearing forces to bags, which are provided in a mixture of wastes. This results from the fact that the tearing elements engage at the bags and ultimately tear the material of the bags because of the relative movement. For this reason, the tearing forces result from the drive power moving the tearing elements.
In addition, the tearing elements cause and/or support to convey the mixture of wastes through the device. In this instance, tearing the material of the bags may result from the individual tearing elements merely gripping onto the bags in the mixture of wastes. The high efficiency of the device or method of the art at issue, however, results largely from the relative movements of the tearing elements of individual groups in relation to one another. Only this relative movement achieves a satisfactory efficiency in regard to the energy input when opening the bags by tearing.
Tearing the material of the bags is to be understood as a tearing in the wider sense, meaning, that a slitting or cutting open of the bags may also occur in this instance, depending on how the specific contact between tearing element and bag materializes. In conjunction with the present invention, all of these processes, in which the tearing elements charge at the material of the bags and at least in places separate said material to open the bags, are, however, subsequently referred to as tearing processes and the forces transferred from the tearing elements to the bags are referred to as tearing forces.
According to the related art established according to the publication EP 0 686 562 B1, the tearing elements are moved in a type of “stop-and-go” operation. This means that a first group of tearing elements first stands still, while a second group of tearing elements moves, by means of which a relative movement between the tearing elements is generated. After a certain time or after running through a specific range of movements, the first group of tearing elements is now also actuated and, after a short common phase of movements, the movement of the second group of tearing elements is halted, by means of which a relative movement between the tearing elements of different groups is in turn generated.
Although it has been shown that bags may be efficiently opened in this manner, owing to the drive power according to the related art expended in this instance, the energy demand of such a device or of such a method is, however, still comparatively high.